Microscopes have long been used for centuries to view pathology specimens placed on microscope slides. The optical system of the microscope can be easily manipulated, and the slide moved around quickly, to allow the field of view to view large areas of the specimen at low magnification or to view smaller areas at greater magnification. This ease of use is important to those who use microscopes.
There has been a strong desire to use digital electronics for all sorts of purposes, including to replicate the behavior of a microscope in the digital world. For that purpose, it has been proposed to take digital images of pathology microscope slides and to store that image for later retrieval such as on a computer screen or other display. Such a so-called digital microscope is considered to present an advance, but current proposals are not sufficient.
Whatever portion of the slide image is to be viewed will typically fill the available screen viewing field, much like the field of view of the microscope. In order to assure that even the smallest portion can be viewed with sufficient clarity and detail, as if at maximum magnification, the entire slide must be imaged at a very high resolution sufficient to provide the necessary detail of every portion thereof. But in reality, it is typical for a pathologist or the like to first want to view the overall slide image, and then to “move” around the image at various levels of magnification to locate those areas that might be of concern.
With current proposals, every time a portion of the image is to be viewed, or even the overall image, a computer processing unit that may form part of a server must take all of that high resolution data for the selected image area, and re-compute a lower resolution version thereof sufficient to fill the viewing area. That process is very computer intensive. While the time involved can often be managed by today's powerful computers, it can still involve some amount of delay between the time the user “moves” the electronic version of the slide around on the screen and selects a magnification level. That delay frustrates the ability to use the digital microscope as a digital replication of traditional microscopes.
The problem becomes even more severe when one desires to view the specimen images on a remote, wireless communication device, such as smart phones, pads, notebooks, or the like. In that case, there is also the further drawback of the communication time involved in communicating the selection from the device to the server and the resend of the image data from the server, thus compounding the delays. Nor is it practical for the wireless communication device in most cases to receive all of the detailed data for maximum resolution of the entire slide image and then compute the data necessary for the selected image area and magnification.